Hardware Accelerated Design of a Dual-Mode Refocusing Algorithm for SAR Imaging Systems
Abstract
:1. Introduction
- (1)
- A novel dual-mode SAR imaging refocusing algorithm that utilizes DCT based on azimuth velocity matching. The algorithm enhances image focus and reduces entropy and contrast.
- (2)
- Lower computational complexity. The optimized speed search for azimuth matching reduces the amount of data by 80%, and the use of binary search further improves search efficiency.
- (3)
- Data enhancement and quantization on the fine refocusing results, compressing data width to 8 bits. The use of a pipeline structure optimizes system performance, balancing speed and resource utilization. The proposed system is implemented on a Xilinx XC5VFX130T FPGA, with simulation results demonstrating two frames per second when processing slice data of real SAR images. The system utilizes significantly less in terms of resources at 69,633 LUTs, 255 RAMs, and 296 DSPs.
2. SAR Imaging Refocusing Model
2.1. Strip Mode Bandpass Filter
2.2. Azimuth Velocity
2.3. Moving Target Fine Focus
3. Refocus System Design
3.1. Parameter Preparation State
3.2. Compensation Phase Calculation State
3.3. Fine Focus State
4. System Optimization
4.1. Fine Focus Result Enhancement and Quantization
4.2. Optimization of Speed Estimation Algorithm
4.3. Timing Optimization
5. System Verification
6. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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State | Description | Software Calculation Time/s | Hardware Calculation Time/ms | Speed Gain |
---|---|---|---|---|
1 | Parameter preparation | 1.1370 | 3.173480 | 358 |
2 | Speed estimation | 0.3020 | 5.638580 | 53 |
3 | Fine focus | 1.1210 | 7.424190 | 151 |
4 | Enhancement and quantization | 1.4310 | 2.206870 | 648 |
Resource | Used | XQ5VFX130T Total Resource | Utilization |
---|---|---|---|
LUT | 46,211 | 81,920 | 55% |
REG | 39,359 | 81,920 | 47% |
RAM | 28 | 298 | 9% |
DSP | 292 | 320 | 90% |
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Yu, L.; Li, Y.; Wu, N. Hardware Accelerated Design of a Dual-Mode Refocusing Algorithm for SAR Imaging Systems. Sensors 2023, 23, 2143. https://doi.org/10.3390/s23042143
Yu L, Li Y, Wu N. Hardware Accelerated Design of a Dual-Mode Refocusing Algorithm for SAR Imaging Systems. Sensors. 2023; 23(4):2143. https://doi.org/10.3390/s23042143
Chicago/Turabian StyleYu, Le, Yaqi Li, and Nansong Wu. 2023. "Hardware Accelerated Design of a Dual-Mode Refocusing Algorithm for SAR Imaging Systems" Sensors 23, no. 4: 2143. https://doi.org/10.3390/s23042143
APA StyleYu, L., Li, Y., & Wu, N. (2023). Hardware Accelerated Design of a Dual-Mode Refocusing Algorithm for SAR Imaging Systems. Sensors, 23(4), 2143. https://doi.org/10.3390/s23042143